[linux-2.6-block.git] / drivers / scsi / sd_dif.c

/*
 * sd_dif.c - SCSI Data Integrity Field
 *
 * Copyright (C) 2007, 2008 Oracle Corporation
 * Written by: Martin K. Petersen <martin.petersen@oracle.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
 * USA.
 *
 */

#include <linux/blkdev.h>
#include <linux/crc-t10dif.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_dbg.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_driver.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsicam.h>

#include <net/checksum.h>

#include "sd.h"

typedef __u16 (csum_fn) (void *, unsigned int);

static __u16 sd_dif_crc_fn(void *data, unsigned int len)
{
	return cpu_to_be16(crc_t10dif(data, len));
}

static __u16 sd_dif_ip_fn(void *data, unsigned int len)
{
	return ip_compute_csum(data, len);
}

/*
 * Type 1 and Type 2 protection use the same format: 16 bit guard tag,
 * 16 bit app tag, 32 bit reference tag.
 */
static void sd_dif_type1_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
{
	void *buf = bix->data_buf;
	struct sd_dif_tuple *sdt = bix->prot_buf;
	sector_t sector = bix->sector;
	unsigned int i;

	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
		sdt->guard_tag = fn(buf, bix->sector_size);
		sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
		sdt->app_tag = 0;

		buf += bix->sector_size;
		sector++;
	}
}

static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix)
{
	sd_dif_type1_generate(bix, sd_dif_crc_fn);
}

static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix)
{
	sd_dif_type1_generate(bix, sd_dif_ip_fn);
}

static int sd_dif_type1_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
{
	void *buf = bix->data_buf;
	struct sd_dif_tuple *sdt = bix->prot_buf;
	sector_t sector = bix->sector;
	unsigned int i;
	__u16 csum;

	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
		/* Unwritten sectors */
		if (sdt->app_tag == 0xffff)
			return 0;

		if (be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
			printk(KERN_ERR
			       "%s: ref tag error on sector %lu (rcvd %u)\n",
			       bix->disk_name, (unsigned long)sector,
			       be32_to_cpu(sdt->ref_tag));
			return -EIO;
		}

		csum = fn(buf, bix->sector_size);

		if (sdt->guard_tag != csum) {
			printk(KERN_ERR "%s: guard tag error on sector %lu " \
			       "(rcvd %04x, data %04x)\n", bix->disk_name,
			       (unsigned long)sector,
			       be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
			return -EIO;
		}

		buf += bix->sector_size;
		sector++;
	}

	return 0;
}

static int sd_dif_type1_verify_crc(struct blk_integrity_exchg *bix)
{
	return sd_dif_type1_verify(bix, sd_dif_crc_fn);
}

static int sd_dif_type1_verify_ip(struct blk_integrity_exchg *bix)
{
	return sd_dif_type1_verify(bix, sd_dif_ip_fn);
}

/*
 * Functions for interleaving and deinterleaving application tags
 */
static void sd_dif_type1_set_tag(void *prot, void *tag_buf, unsigned int sectors)
{
	struct sd_dif_tuple *sdt = prot;
	u8 *tag = tag_buf;
	unsigned int i, j;

	for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
		sdt->app_tag = tag[j] << 8 | tag[j+1];
		BUG_ON(sdt->app_tag == 0xffff);
	}
}

static void sd_dif_type1_get_tag(void *prot, void *tag_buf, unsigned int sectors)
{
	struct sd_dif_tuple *sdt = prot;
	u8 *tag = tag_buf;
	unsigned int i, j;

	for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
		tag[j] = (sdt->app_tag & 0xff00) >> 8;
		tag[j+1] = sdt->app_tag & 0xff;
	}
}

static struct blk_integrity dif_type1_integrity_crc = {
	.name			= "T10-DIF-TYPE1-CRC",
	.generate_fn		= sd_dif_type1_generate_crc,
	.verify_fn		= sd_dif_type1_verify_crc,
	.get_tag_fn		= sd_dif_type1_get_tag,
	.set_tag_fn		= sd_dif_type1_set_tag,
	.tuple_size		= sizeof(struct sd_dif_tuple),
	.tag_size		= 0,
};

static struct blk_integrity dif_type1_integrity_ip = {
	.name			= "T10-DIF-TYPE1-IP",
	.generate_fn		= sd_dif_type1_generate_ip,
	.verify_fn		= sd_dif_type1_verify_ip,
	.get_tag_fn		= sd_dif_type1_get_tag,
	.set_tag_fn		= sd_dif_type1_set_tag,
	.tuple_size		= sizeof(struct sd_dif_tuple),
	.tag_size		= 0,
};


/*
 * Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
 * tag space.
 */
static void sd_dif_type3_generate(struct blk_integrity_exchg *bix, csum_fn *fn)
{
	void *buf = bix->data_buf;
	struct sd_dif_tuple *sdt = bix->prot_buf;
	unsigned int i;

	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
		sdt->guard_tag = fn(buf, bix->sector_size);
		sdt->ref_tag = 0;
		sdt->app_tag = 0;

		buf += bix->sector_size;
	}
}

static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix)
{
	sd_dif_type3_generate(bix, sd_dif_crc_fn);
}

static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix)
{
	sd_dif_type3_generate(bix, sd_dif_ip_fn);
}

static int sd_dif_type3_verify(struct blk_integrity_exchg *bix, csum_fn *fn)
{
	void *buf = bix->data_buf;
	struct sd_dif_tuple *sdt = bix->prot_buf;
	sector_t sector = bix->sector;
	unsigned int i;
	__u16 csum;

	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
		/* Unwritten sectors */
		if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff)
			return 0;

		csum = fn(buf, bix->sector_size);

		if (sdt->guard_tag != csum) {
			printk(KERN_ERR "%s: guard tag error on sector %lu " \
			       "(rcvd %04x, data %04x)\n", bix->disk_name,
			       (unsigned long)sector,
			       be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
			return -EIO;
		}

		buf += bix->sector_size;
		sector++;
	}

	return 0;
}

static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix)
{
	return sd_dif_type3_verify(bix, sd_dif_crc_fn);
}

static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix)
{
	return sd_dif_type3_verify(bix, sd_dif_ip_fn);
}

static void sd_dif_type3_set_tag(void *prot, void *tag_buf, unsigned int sectors)
{
	struct sd_dif_tuple *sdt = prot;
	u8 *tag = tag_buf;
	unsigned int i, j;

	for (i = 0, j = 0 ; i < sectors ; i++, j += 6, sdt++) {
		sdt->app_tag = tag[j] << 8 | tag[j+1];
		sdt->ref_tag = tag[j+2] << 24 | tag[j+3] << 16 |
			tag[j+4] << 8 | tag[j+5];
	}
}

static void sd_dif_type3_get_tag(void *prot, void *tag_buf, unsigned int sectors)
{
	struct sd_dif_tuple *sdt = prot;
	u8 *tag = tag_buf;
	unsigned int i, j;

	for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
		tag[j] = (sdt->app_tag & 0xff00) >> 8;
		tag[j+1] = sdt->app_tag & 0xff;
		tag[j+2] = (sdt->ref_tag & 0xff000000) >> 24;
		tag[j+3] = (sdt->ref_tag & 0xff0000) >> 16;
		tag[j+4] = (sdt->ref_tag & 0xff00) >> 8;
		tag[j+5] = sdt->ref_tag & 0xff;
		BUG_ON(sdt->app_tag == 0xffff || sdt->ref_tag == 0xffffffff);
	}
}

static struct blk_integrity dif_type3_integrity_crc = {
	.name			= "T10-DIF-TYPE3-CRC",
	.generate_fn		= sd_dif_type3_generate_crc,
	.verify_fn		= sd_dif_type3_verify_crc,
	.get_tag_fn		= sd_dif_type3_get_tag,
	.set_tag_fn		= sd_dif_type3_set_tag,
	.tuple_size		= sizeof(struct sd_dif_tuple),
	.tag_size		= 0,
};

static struct blk_integrity dif_type3_integrity_ip = {
	.name			= "T10-DIF-TYPE3-IP",
	.generate_fn		= sd_dif_type3_generate_ip,
	.verify_fn		= sd_dif_type3_verify_ip,
	.get_tag_fn		= sd_dif_type3_get_tag,
	.set_tag_fn		= sd_dif_type3_set_tag,
	.tuple_size		= sizeof(struct sd_dif_tuple),
	.tag_size		= 0,
};

/*
 * Configure exchange of protection information between OS and HBA.
 */
void sd_dif_config_host(struct scsi_disk *sdkp)
{
	struct scsi_device *sdp = sdkp->device;
	struct gendisk *disk = sdkp->disk;
	u8 type = sdkp->protection_type;
	int dif, dix;

	dif = scsi_host_dif_capable(sdp->host, type);
	dix = scsi_host_dix_capable(sdp->host, type);

	if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
		dif = 0; dix = 1;
	}

	if (!dix)
		return;

	/* Enable DMA of protection information */
	if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
		if (type == SD_DIF_TYPE3_PROTECTION)
			blk_integrity_register(disk, &dif_type3_integrity_ip);
		else
			blk_integrity_register(disk, &dif_type1_integrity_ip);
	else
		if (type == SD_DIF_TYPE3_PROTECTION)
			blk_integrity_register(disk, &dif_type3_integrity_crc);
		else
			blk_integrity_register(disk, &dif_type1_integrity_crc);

	sd_printk(KERN_NOTICE, sdkp,
		  "Enabling DIX %s protection\n", disk->integrity->name);

	/* Signal to block layer that we support sector tagging */
	if (dif && type && sdkp->ATO) {
		if (type == SD_DIF_TYPE3_PROTECTION)
			disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
		else
			disk->integrity->tag_size = sizeof(u16);

		sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
			  disk->integrity->tag_size);
	}
}

/*
 * The virtual start sector is the one that was originally submitted
 * by the block layer.	Due to partitioning, MD/DM cloning, etc. the
 * actual physical start sector is likely to be different.  Remap
 * protection information to match the physical LBA.
 *
 * From a protocol perspective there's a slight difference between
 * Type 1 and 2.  The latter uses 32-byte CDBs exclusively, and the
 * reference tag is seeded in the CDB.  This gives us the potential to
 * avoid virt->phys remapping during write.  However, at read time we
 * don't know whether the virt sector is the same as when we wrote it
 * (we could be reading from real disk as opposed to MD/DM device.  So
 * we always remap Type 2 making it identical to Type 1.
 *
 * Type 3 does not have a reference tag so no remapping is required.
 */
void sd_dif_prepare(struct request *rq, sector_t hw_sector,
		    unsigned int sector_sz)
{
	const int tuple_sz = sizeof(struct sd_dif_tuple);
	struct bio *bio;
	struct scsi_disk *sdkp;
	struct sd_dif_tuple *sdt;
	u32 phys, virt;

	sdkp = rq->bio->bi_bdev->bd_disk->private_data;

	if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
		return;

	phys = hw_sector & 0xffffffff;

	__rq_for_each_bio(bio, rq) {
		struct bio_vec iv;
		struct bvec_iter iter;
		unsigned int j;

		/* Already remapped? */
		if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
			break;

		virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;

		bip_for_each_vec(iv, bio->bi_integrity, iter) {
			sdt = kmap_atomic(iv.bv_page)
				+ iv.bv_offset;

			for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {

				if (be32_to_cpu(sdt->ref_tag) == virt)
					sdt->ref_tag = cpu_to_be32(phys);

				virt++;
				phys++;
			}

			kunmap_atomic(sdt);
		}

		bio->bi_flags |= (1 << BIO_MAPPED_INTEGRITY);
	}
}

/*
 * Remap physical sector values in the reference tag to the virtual
 * values expected by the block layer.
 */
void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
{
	const int tuple_sz = sizeof(struct sd_dif_tuple);
	struct scsi_disk *sdkp;
	struct bio *bio;
	struct sd_dif_tuple *sdt;
	unsigned int j, sectors, sector_sz;
	u32 phys, virt;

	sdkp = scsi_disk(scmd->request->rq_disk);

	if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION || good_bytes == 0)
		return;

	sector_sz = scmd->device->sector_size;
	sectors = good_bytes / sector_sz;

	phys = blk_rq_pos(scmd->request) & 0xffffffff;
	if (sector_sz == 4096)
		phys >>= 3;

	__rq_for_each_bio(bio, scmd->request) {
		struct bio_vec iv;
		struct bvec_iter iter;

		virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;

		bip_for_each_vec(iv, bio->bi_integrity, iter) {
			sdt = kmap_atomic(iv.bv_page)
				+ iv.bv_offset;

			for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {

				if (sectors == 0) {
					kunmap_atomic(sdt);
					return;
				}

				if (be32_to_cpu(sdt->ref_tag) == phys)
					sdt->ref_tag = cpu_to_be32(virt);

				virt++;
				phys++;
				sectors--;
			}

			kunmap_atomic(sdt);
		}
	}
}
Commit	Line	Data
af55ff67 MP	1	/*
	2	* sd_dif.c - SCSI Data Integrity Field
	3	*
	4	* Copyright (C) 2007, 2008 Oracle Corporation
	5	* Written by: Martin K. Petersen <martin.petersen@oracle.com>
	6	*
	7	* This program is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU General Public License version
	9	* 2 as published by the Free Software Foundation.
	10	*
	11	* This program is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; see the file COPYING. If not, write to
	18	* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
	19	* USA.
	20	*
	21	*/
	22
	23	#include <linux/blkdev.h>
	24	#include <linux/crc-t10dif.h>
	25
	26	#include <scsi/scsi.h>
	27	#include <scsi/scsi_cmnd.h>
	28	#include <scsi/scsi_dbg.h>
	29	#include <scsi/scsi_device.h>
	30	#include <scsi/scsi_driver.h>
	31	#include <scsi/scsi_eh.h>
	32	#include <scsi/scsi_host.h>
	33	#include <scsi/scsi_ioctl.h>
	34	#include <scsi/scsicam.h>
	35
	36	#include <net/checksum.h>
	37
	38	#include "sd.h"
	39
	40	typedef __u16 (csum_fn) (void *, unsigned int);
	41
	42	static __u16 sd_dif_crc_fn(void *data, unsigned int len)
	43	{
	44	return cpu_to_be16(crc_t10dif(data, len));
	45	}
	46
	47	static __u16 sd_dif_ip_fn(void *data, unsigned int len)
	48	{
	49	return ip_compute_csum(data, len);
	50	}
	51
	52	/*
	53	* Type 1 and Type 2 protection use the same format: 16 bit guard tag,
	54	* 16 bit app tag, 32 bit reference tag.
	55	*/
	56	static void sd_dif_type1_generate(struct blk_integrity_exchg bix, csum_fn fn)
	57	{
	58	void *buf = bix->data_buf;
	59	struct sd_dif_tuple *sdt = bix->prot_buf;
	60	sector_t sector = bix->sector;
	61	unsigned int i;
	62
	63	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
	64	sdt->guard_tag = fn(buf, bix->sector_size);
65	sdt->ref_tag = cpu_to_be32(sector & 0xffffffff);
66	sdt->app_tag = 0;
67
68	buf += bix->sector_size;
69	sector++;
70	}
71	}
72
73	static void sd_dif_type1_generate_crc(struct blk_integrity_exchg *bix)
74	{
75	sd_dif_type1_generate(bix, sd_dif_crc_fn);
76	}
77
78	static void sd_dif_type1_generate_ip(struct blk_integrity_exchg *bix)
79	{
80	sd_dif_type1_generate(bix, sd_dif_ip_fn);
81	}
82
83	static int sd_dif_type1_verify(struct blk_integrity_exchg bix, csum_fn fn)
84	{
85	void *buf = bix->data_buf;
86	struct sd_dif_tuple *sdt = bix->prot_buf;
87	sector_t sector = bix->sector;
88	unsigned int i;
89	__u16 csum;
90
91	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
92	/* Unwritten sectors */
93	if (sdt->app_tag == 0xffff)
94	return 0;
95
af55ff67 MP	96	if (be32_to_cpu(sdt->ref_tag) != (sector & 0xffffffff)) {
	97	printk(KERN_ERR
	98	"%s: ref tag error on sector %lu (rcvd %u)\n",
	99	bix->disk_name, (unsigned long)sector,
	100	be32_to_cpu(sdt->ref_tag));
	101	return -EIO;
	102	}
	103
	104	csum = fn(buf, bix->sector_size);
	105
	106	if (sdt->guard_tag != csum) {
	107	printk(KERN_ERR "%s: guard tag error on sector %lu " \
	108	"(rcvd %04x, data %04x)\n", bix->disk_name,
	109	(unsigned long)sector,
	110	be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
	111	return -EIO;
	112	}
	113
	114	buf += bix->sector_size;
	115	sector++;
	116	}
	117
	118	return 0;
	119	}
	120
	121	static int sd_dif_type1_verify_crc(struct blk_integrity_exchg *bix)
	122	{
	123	return sd_dif_type1_verify(bix, sd_dif_crc_fn);
	124	}
	125
	126	static int sd_dif_type1_verify_ip(struct blk_integrity_exchg *bix)
	127	{
	128	return sd_dif_type1_verify(bix, sd_dif_ip_fn);
	129	}
	130
	131	/*
	132	* Functions for interleaving and deinterleaving application tags
	133	*/
	134	static void sd_dif_type1_set_tag(void prot, void tag_buf, unsigned int sectors)
	135	{
	136	struct sd_dif_tuple *sdt = prot;
becce74b	137	u8 *tag = tag_buf;
af55ff67 MP	138	unsigned int i, j;
	139
	140	for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
	141	sdt->app_tag = tag[j] << 8 \| tag[j+1];
	142	BUG_ON(sdt->app_tag == 0xffff);
	143	}
	144	}
	145
	146	static void sd_dif_type1_get_tag(void prot, void tag_buf, unsigned int sectors)
	147	{
	148	struct sd_dif_tuple *sdt = prot;
becce74b	149	u8 *tag = tag_buf;
af55ff67 MP	150	unsigned int i, j;
	151
	152	for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
	153	tag[j] = (sdt->app_tag & 0xff00) >> 8;
	154	tag[j+1] = sdt->app_tag & 0xff;
	155	}
	156	}
	157
	158	static struct blk_integrity dif_type1_integrity_crc = {
	159	.name = "T10-DIF-TYPE1-CRC",
	160	.generate_fn = sd_dif_type1_generate_crc,
	161	.verify_fn = sd_dif_type1_verify_crc,
	162	.get_tag_fn = sd_dif_type1_get_tag,
	163	.set_tag_fn = sd_dif_type1_set_tag,
	164	.tuple_size = sizeof(struct sd_dif_tuple),
	165	.tag_size = 0,
	166	};
	167
	168	static struct blk_integrity dif_type1_integrity_ip = {
	169	.name = "T10-DIF-TYPE1-IP",
	170	.generate_fn = sd_dif_type1_generate_ip,
	171	.verify_fn = sd_dif_type1_verify_ip,
	172	.get_tag_fn = sd_dif_type1_get_tag,
	173	.set_tag_fn = sd_dif_type1_set_tag,
	174	.tuple_size = sizeof(struct sd_dif_tuple),
	175	.tag_size = 0,
	176	};
	177
	178
	179	/*
	180	* Type 3 protection has a 16-bit guard tag and 16 + 32 bits of opaque
	181	* tag space.
	182	*/
	183	static void sd_dif_type3_generate(struct blk_integrity_exchg bix, csum_fn fn)
	184	{
	185	void *buf = bix->data_buf;
	186	struct sd_dif_tuple *sdt = bix->prot_buf;
	187	unsigned int i;
	188
	189	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
	190	sdt->guard_tag = fn(buf, bix->sector_size);
	191	sdt->ref_tag = 0;
	192	sdt->app_tag = 0;
	193
	194	buf += bix->sector_size;
	195	}
	196	}
	197
	198	static void sd_dif_type3_generate_crc(struct blk_integrity_exchg *bix)
	199	{
	200	sd_dif_type3_generate(bix, sd_dif_crc_fn);
	201	}
	202
	203	static void sd_dif_type3_generate_ip(struct blk_integrity_exchg *bix)
	204	{
	205	sd_dif_type3_generate(bix, sd_dif_ip_fn);
	206	}
	207
	208	static int sd_dif_type3_verify(struct blk_integrity_exchg bix, csum_fn fn)
	209	{
	210	void *buf = bix->data_buf;
	211	struct sd_dif_tuple *sdt = bix->prot_buf;
	212	sector_t sector = bix->sector;
	213	unsigned int i;
214	__u16 csum;
215
216	for (i = 0 ; i < bix->data_size ; i += bix->sector_size, sdt++) {
217	/* Unwritten sectors */
218	if (sdt->app_tag == 0xffff && sdt->ref_tag == 0xffffffff)
219	return 0;
220
221	csum = fn(buf, bix->sector_size);
222
223	if (sdt->guard_tag != csum) {
224	printk(KERN_ERR "%s: guard tag error on sector %lu " \
225	"(rcvd %04x, data %04x)\n", bix->disk_name,
226	(unsigned long)sector,
227	be16_to_cpu(sdt->guard_tag), be16_to_cpu(csum));
228	return -EIO;
229	}
230
231	buf += bix->sector_size;
232	sector++;
233	}
234
235	return 0;
236	}
237
238	static int sd_dif_type3_verify_crc(struct blk_integrity_exchg *bix)
239	{
240	return sd_dif_type3_verify(bix, sd_dif_crc_fn);
241	}
242
243	static int sd_dif_type3_verify_ip(struct blk_integrity_exchg *bix)
244	{
245	return sd_dif_type3_verify(bix, sd_dif_ip_fn);
246	}
247
248	static void sd_dif_type3_set_tag(void prot, void tag_buf, unsigned int sectors)
249	{
250	struct sd_dif_tuple *sdt = prot;
becce74b	251	u8 *tag = tag_buf;
af55ff67 MP	252	unsigned int i, j;
	253
	254	for (i = 0, j = 0 ; i < sectors ; i++, j += 6, sdt++) {
	255	sdt->app_tag = tag[j] << 8 \| tag[j+1];
	256	sdt->ref_tag = tag[j+2] << 24 \| tag[j+3] << 16 \|
	257	tag[j+4] << 8 \| tag[j+5];
	258	}
	259	}
	260
	261	static void sd_dif_type3_get_tag(void prot, void tag_buf, unsigned int sectors)
	262	{
	263	struct sd_dif_tuple *sdt = prot;
becce74b	264	u8 *tag = tag_buf;
af55ff67 MP	265	unsigned int i, j;
	266
	267	for (i = 0, j = 0 ; i < sectors ; i++, j += 2, sdt++) {
	268	tag[j] = (sdt->app_tag & 0xff00) >> 8;
	269	tag[j+1] = sdt->app_tag & 0xff;
	270	tag[j+2] = (sdt->ref_tag & 0xff000000) >> 24;
	271	tag[j+3] = (sdt->ref_tag & 0xff0000) >> 16;
	272	tag[j+4] = (sdt->ref_tag & 0xff00) >> 8;
	273	tag[j+5] = sdt->ref_tag & 0xff;
	274	BUG_ON(sdt->app_tag == 0xffff \|\| sdt->ref_tag == 0xffffffff);
	275	}
	276	}
	277
	278	static struct blk_integrity dif_type3_integrity_crc = {
	279	.name = "T10-DIF-TYPE3-CRC",
	280	.generate_fn = sd_dif_type3_generate_crc,
	281	.verify_fn = sd_dif_type3_verify_crc,
	282	.get_tag_fn = sd_dif_type3_get_tag,
	283	.set_tag_fn = sd_dif_type3_set_tag,
	284	.tuple_size = sizeof(struct sd_dif_tuple),
	285	.tag_size = 0,
	286	};
	287
	288	static struct blk_integrity dif_type3_integrity_ip = {
	289	.name = "T10-DIF-TYPE3-IP",
	290	.generate_fn = sd_dif_type3_generate_ip,
	291	.verify_fn = sd_dif_type3_verify_ip,
	292	.get_tag_fn = sd_dif_type3_get_tag,
	293	.set_tag_fn = sd_dif_type3_set_tag,
	294	.tuple_size = sizeof(struct sd_dif_tuple),
	295	.tag_size = 0,
	296	};
	297
	298	/*
	299	* Configure exchange of protection information between OS and HBA.
	300	*/
	301	void sd_dif_config_host(struct scsi_disk *sdkp)
	302	{
	303	struct scsi_device *sdp = sdkp->device;
	304	struct gendisk *disk = sdkp->disk;
	305	u8 type = sdkp->protection_type;
9e06688e	306	int dif, dix;
af55ff67	307
9e06688e MP	308	dif = scsi_host_dif_capable(sdp->host, type);
9e06688e MP	309	dix = scsi_host_dix_capable(sdp->host, type);
af55ff67	310
9e06688e MP	311	if (!dix && scsi_host_dix_capable(sdp->host, 0)) {
	312	dif = 0; dix = 1;
	313	}
af55ff67	314
9e06688e	315	if (!dix)
af55ff67	316	return;
af55ff67 MP	317
	318	/* Enable DMA of protection information */
	319	if (scsi_host_get_guard(sdkp->device->host) & SHOST_DIX_GUARD_IP)
	320	if (type == SD_DIF_TYPE3_PROTECTION)
	321	blk_integrity_register(disk, &dif_type3_integrity_ip);
	322	else
	323	blk_integrity_register(disk, &dif_type1_integrity_ip);
	324	else
	325	if (type == SD_DIF_TYPE3_PROTECTION)
	326	blk_integrity_register(disk, &dif_type3_integrity_crc);
	327	else
	328	blk_integrity_register(disk, &dif_type1_integrity_crc);
	329
cbdc1445	330	sd_printk(KERN_NOTICE, sdkp,
9e06688e	331	"Enabling DIX %s protection\n", disk->integrity->name);
af55ff67 MP	332
af55ff67 MP	333	/* Signal to block layer that we support sector tagging */
9e06688e	334	if (dif && type && sdkp->ATO) {
af55ff67 MP	335	if (type == SD_DIF_TYPE3_PROTECTION)
	336	disk->integrity->tag_size = sizeof(u16) + sizeof(u32);
	337	else
	338	disk->integrity->tag_size = sizeof(u16);
	339
cbdc1445	340	sd_printk(KERN_NOTICE, sdkp, "DIF application tag size %u\n",
af55ff67 MP	341	disk->integrity->tag_size);
	342	}
	343	}
	344
af55ff67 MP	345	/*
	346	* The virtual start sector is the one that was originally submitted
	347	* by the block layer. Due to partitioning, MD/DM cloning, etc. the
	348	* actual physical start sector is likely to be different. Remap
	349	* protection information to match the physical LBA.
	350	*
	351	* From a protocol perspective there's a slight difference between
	352	* Type 1 and 2. The latter uses 32-byte CDBs exclusively, and the
	353	* reference tag is seeded in the CDB. This gives us the potential to
	354	* avoid virt->phys remapping during write. However, at read time we
	355	* don't know whether the virt sector is the same as when we wrote it
	356	* (we could be reading from real disk as opposed to MD/DM device. So
	357	* we always remap Type 2 making it identical to Type 1.
	358	*
	359	* Type 3 does not have a reference tag so no remapping is required.
	360	*/
8c579ab6 MP	361	void sd_dif_prepare(struct request *rq, sector_t hw_sector,
8c579ab6 MP	362	unsigned int sector_sz)
af55ff67 MP	363	{
	364	const int tuple_sz = sizeof(struct sd_dif_tuple);
	365	struct bio *bio;
	366	struct scsi_disk *sdkp;
	367	struct sd_dif_tuple *sdt;
af55ff67 MP	368	u32 phys, virt;
af55ff67 MP	369
af55ff67 MP	370	sdkp = rq->bio->bi_bdev->bd_disk->private_data;
	371
	372	if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION)
8c579ab6	373	return;
af55ff67	374
af55ff67 MP	375	phys = hw_sector & 0xffffffff;
	376
	377	__rq_for_each_bio(bio, rq) {
d57a5f7c KO	378	struct bio_vec iv;
	379	struct bvec_iter iter;
	380	unsigned int j;
af55ff67	381
495d2b38 MP	382	/* Already remapped? */
	383	if (bio_flagged(bio, BIO_MAPPED_INTEGRITY))
	384	break;
	385
d57a5f7c	386	virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
af55ff67	387
d57a5f7c KO	388	bip_for_each_vec(iv, bio->bi_integrity, iter) {
	389	sdt = kmap_atomic(iv.bv_page)
	390	+ iv.bv_offset;
af55ff67	391
d57a5f7c	392	for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
af55ff67	393
8c579ab6 MP	394	if (be32_to_cpu(sdt->ref_tag) == virt)
8c579ab6 MP	395	sdt->ref_tag = cpu_to_be32(phys);
af55ff67	396
af55ff67 MP	397	virt++;
	398	phys++;
	399	}
	400
77dfce07	401	kunmap_atomic(sdt);
af55ff67	402	}
495d2b38	403
9354f1b8	404	bio->bi_flags \|= (1 << BIO_MAPPED_INTEGRITY);
af55ff67	405	}
af55ff67 MP	406	}
	407
	408	/*
	409	* Remap physical sector values in the reference tag to the virtual
	410	* values expected by the block layer.
	411	*/
	412	void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
	413	{
	414	const int tuple_sz = sizeof(struct sd_dif_tuple);
	415	struct scsi_disk *sdkp;
	416	struct bio *bio;
	417	struct sd_dif_tuple *sdt;
d57a5f7c	418	unsigned int j, sectors, sector_sz;
af55ff67 MP	419	u32 phys, virt;
	420
	421	sdkp = scsi_disk(scmd->request->rq_disk);
	422
	423	if (sdkp->protection_type == SD_DIF_TYPE3_PROTECTION \|\| good_bytes == 0)
	424	return;
	425
	426	sector_sz = scmd->device->sector_size;
	427	sectors = good_bytes / sector_sz;
	428
83096ebf	429	phys = blk_rq_pos(scmd->request) & 0xffffffff;
af55ff67 MP	430	if (sector_sz == 4096)
	431	phys >>= 3;
	432
	433	__rq_for_each_bio(bio, scmd->request) {
d57a5f7c KO	434	struct bio_vec iv;
d57a5f7c KO	435	struct bvec_iter iter;
af55ff67	436
d57a5f7c	437	virt = bio->bi_integrity->bip_iter.bi_sector & 0xffffffff;
af55ff67	438
d57a5f7c KO	439	bip_for_each_vec(iv, bio->bi_integrity, iter) {
	440	sdt = kmap_atomic(iv.bv_page)
	441	+ iv.bv_offset;
af55ff67	442
d57a5f7c	443	for (j = 0; j < iv.bv_len; j += tuple_sz, sdt++) {
af55ff67 MP	444
af55ff67 MP	445	if (sectors == 0) {
77dfce07	446	kunmap_atomic(sdt);
af55ff67 MP	447	return;
	448	}
	449
8c579ab6	450	if (be32_to_cpu(sdt->ref_tag) == phys)
af55ff67 MP	451	sdt->ref_tag = cpu_to_be32(virt);
	452
	453	virt++;
	454	phys++;
	455	sectors--;
	456	}
	457
77dfce07	458	kunmap_atomic(sdt);
af55ff67 MP	459	}
	460	}
	461	}
	462